If you're going from Disney resort to Disney resort just call bell services the night before and ask them to transfer your bags in the morning.
It's supposed to be easy but the one time we did it it wasn't. We were going from CBR to BC. They said "no problem. We'll pick up your luggage at 9am and it will be delivered to BC by 1pm." At 9am no one showed up. We called down and they had no idea what we were talking about. Someone finally came and got our luggage. It showed up at BC at 5pm.
I have read other posts and it seems to usually go better than this. Good luck.